1. Field of the Invention
Apparatuses and methods consistent with the present invention relate to a method for generating a signal and an image display apparatus using the same, and more particularly, to a method for generating a signal to display a three-dimensional (3D) image, and an image display apparatus using the same.
2. Description of the Related Art
Three dimensional (3D) image display technology is applied in a wide variety of fields, including communications, broadcasting, medical services, education, the military, computer games, computer animation, virtual reality, computer-aided design (CAD), industrial technology, or the like, and is at the core of current development for the next generation of information communication, for which there is currently a highly competitive development environment.
A person perceives a 3D effect due to various reasons, including variations in the thickness of the lenses of his or her eyes, the angle between his or her eyes and the subject, the position of the subject as viewed through both eyes, the parallax caused by the motion of the subject, and psychological effects.
Binocular disparity, which refers to the difference between the images of an object as seen by the left and right eyes due to the horizontal separation of the eyes by about 6 to 7 cm, is the most important factor in producing a three-dimensional feeling. The left and right eyes see different two dimensional images which are transmitted to the brain through the retina. The brain then fuses these two different images with great accuracy to reproduce the sense of a three-dimensional image.
3D image display apparatuses may be divided into glass type and non-glass type apparatuses. Glass type apparatuses include a color filter type apparatus which filters an image using a color filter including complementary color filter segments, a polarizing filter type apparatus which divides an image into a left eye image and a right eye image using a shading effect caused by a polarized light element, the directions of which are orthogonal to each other, and a shutter glass type apparatus which blocks a left eye and right eye alternately to correspond to a synchronization signal.
Shutter glass type apparatuses use different perspectives for each eye, which provides an image on the display device while turning each eye on or off, so that the user perceives a sense of space from an image viewed at different angles.
However, not only must a user wear shutter glasses, but also the display device is synchronized wirelessly with the shutter glasses in order to display a 3D image. If the display device temporarily fails to be synchronized with the shutter glasses, it is impossible for the user to view a 3D image.